Furnace fire box and arch structure



April 2, 1935. J C CHAPPLE 1,996,058

FURNACE FIRE BOX AND ARCH STRUCTURE Filed May 29, 1931 2 Sheets-Sheet 11 INVENTOR.

K/ W M TTONEY April 2, 1935. .1. c. CHAPPLE' V FURNACE FIRE EOX-AND ARCHSTRUCTURE' Filed May 29, 1931 2 Sheets-Sheet 2 INVENTOR. I [fidfifi/cf.- M

Jda ATTORNEY I Patented Apr. 2, 1935 UNITED FURNACE FIRE Box'AND anonSTRUCTURE John 0. iChapple, St. Louis, Mo. 7 ,7 Application May 29,1931,- Serial No. 540,948 sloiaims. (or. 122- 68) spect is moreparticularly characterized by an improved type of watercirculatingelement ,extending through the fire box upon which the arch is supportedso constructed as to obviate the formation of steam holding or retainingpockets.

It is also another object of the invention to provide the firebox withone or more siphons extending between the throat sheet and crown sheetthereof and water circulating means connecting the rear ends of thesiphons with the fire door sheet. I I A further object of the inventionin one form thereof resides in the --provision of an auxiliary archsupported upon'the water circulating tubes in rearwardly spacedrelationto the main arch for the purpose of retarding the :flow of theprodnets of combustion rearwardly above said main arch thereby obtaininga comparatively .pro longed heating effect uponthe fire door sheet andcrown sheet of the firebox.

With the above and other objects in view, the invention consists in theimproved furnace fire box and arch structure as will be hereinafter morefully described, illustrated in the accompanying drawings, andsubsequently incorporated in the subjoined claims.

In the drawings, wherein I have disclosedtwo simple andpracticalembodiments of the essential features of my improvements, in whichsimilar reference characters designate corresponding parts throughoutthe -severalviews,,

Fig. l. is a vertical section through alocomotive fire box, thisviewbeing taken on theline I-! of Fig. 2, and illustrating theapplication of the arch structure to an alternating arrangement of watercirculating tubes and siphons;

Fig. 2 is a sectional view taken substantially 0n the line 2--2'of'Fig'. 1, the ends ofthe-arch tubes and the fire'boxwall being shownin elevation;

Fig.3 is a vertical rsection taken substantially onithe line :3.-*-;3 ofFig. .4, showing anotherl em- .wlihbodimentof theinvention; i.

. i Fig. 4 is a vertical sectionalview taken onthe line 4 -l of Fig. 3,theends of the arch tubes .and the firebox wall being shown inelevation,and

Fig. 5 is a detail perspectiveview of one of the spacer brick used inthe auxiliary arch shown .inFig.3.- v

Modern high powered locomotives are provided with boiler fire boxes ofappreciably-greater length than those heretofore used instandardlocomotive boiler construction, and ifthe con-1 ventionaltypeofarch-isproportionately extend-- edrearwardly towards the fireboxdoorsheehthe space between the top of the arch and thec'rown sheet istoo greatly restricted. If'the comparatively short arch is used, theproducts of' .combustion pass over the rear end of the archfor- Wardlyto the boiler ,fl'ues togetherQwith considerable fineooaluni'gnitedoronIY partially co'ntsu-med .and are not brought intocontact-with the l fire door sheet and rear portionsof the side sheets.a and crown sheet of the fire box. This results inadequate steamproduction and uneconomical consumption of fuel. Ina co-pendi-ngapplication for patentfiled of even .dateherewith, ,I have disclosed animproved arch structure for uselin connection with relatively long fireboxes having its upper rear end embodying means .fordeflecting theproducts ofcombustion downwardly towards the fuel bed and in contactwith the rear side sheets, fire door sheet and C10WIfl She ellq-Qf v thefire box and which obviates undue .restriction of the space between thetop of the archand the crown sheet. :In order to enablelthi s arch to-beused in conjunctionwith water circulatingitubes and siphons of,conventional form, I have dis- 735 closed in said application,refractory tile or brick constituting the upper end of the arch of acertain novel form and-construction- ,I propose, by means of mypresentinvention to accomplish this same general result with ,the use of anarch composed Wholly .of refractory bricks j or units of standard form.g

In the drawings wherein Ihave illustrated-the essential featureof myinvention-as applied-to a locomotive fire box, 5 designates the firedoor sheet at the rear end of the fire box, 6 the flue sheet at theforward end thereof, 8 the crown sheet, and 9 the throat sheet extendingu downwar dly from the flue sheet in rearwardly ofiset relation thereto.In these respects, the boiler 5 o fire box is of conventional form, andit will there fore, foe understood that the boilerwater sur: rounds andis in direct contact with theaQflter surfaces of these metal wallsorsheetsof; the fire obliquely inclined water circulatingtubesextendlongitudinally through the fire box fromthe throat sheetQtothe fire door sheet 5, As herein 7 shown, each of these tubesincludes a rear section- I0 opening'at its lower end through the throatsheet 9, said tube section having a lower portion 10f somewhat'greaterradius than the upper portion thereof to provide longitudinallyextending shoulders II oneach side of said tube section.

The upper end of the tube section I llon its lower. side, islongitudinally curved as indicated at I2, the shoulders I I extendingthroughout this curved part of the tube in concentric relation thereto.Thejupper portion of the tube at this curvedsection I2graduallym'ergesinto the vertically elon jgatedorrfiattened uppersection of the tube' which opens at its upper end: throughthe firedoorsheet 5 adjacent tothe'crownsheet'fl. The walls :of the lower curvedportion J2 o f'the"tube* land the shoulders. I I are gradually mergedinto the opposite side walls of'the flattened tubesections I3 so as toavoidithe'forrnation of, internal stearn holding or retainingpockets inthe tube wallsp a H "In' Figs; *1 and-2 of the-drawings; I have shownvertically disposed siphons I6 within thefire box alternately arrangedwith respect to'the watercir'cul atinlg tubes of the form abovedescribed.

,"These 'siphons have: upper longitudinally elongated portions whichopenthrough the crown sheet 18, andatthei'r lowergends are provided with"forwardly andfdo'wnwardly, extending tubular ofthesiphons, the lowerends thereof are of the V I same cross'sectional form and arelongitudinally k V a v :tubes, as will be evident from reference to thedrawings. H'I'helo'wer portion of the siphon and portions openingthrough! the throat sheet 9. These tubularjportions are of the samecrosssec- "'tional'formas the portions I0 of the water-circulating tubesand disposed in the same plane therewith; Also above these tubularextensions curve'd'in the same manner as the parts I2 of the 'itslforward tubular extension are provided with shouldersII' on oppositesides thereof to receive and support one end of the arch bricks- I4which extend between the siphon and water-circulatingtubes; V I

Thus it will be seen that a series ofv alternating the adjacent watercirculating tubes and siphons in any desired number may be arranged intransversely spaced relation through the fire box and uponthe shouldersII and" I-I- of these spaced tubes and siphons, respectively,'the archforming brick *or tile of refractory material indicated at I4 beeingisupported-at theiropposite ends, thus pre- -venting"the directpassage of the products of combustion upwardly between the tubes andsiphons in thisportion of the firebox and causing the same to flowlongitudinally along and in contact with said tubes and siphons in therear'ends. of the arch-wall. The brick I4 are I ,of'a standardformwidely'used in such locomo tive arches; having upper and lower'c'urved surfaces with the lower concave surfacesjthereof 'opposedto'thefuel bed. As seenin Figs. land 2 of Y the drawings; by reason of thecurvedrear end portions of the shoulders'II and II" of the V supportingtubes and siphons, the brick forming therear end of the arch wall willbesuccess'ively supported at different angles and together, form"a"rearwardly extending downwardly curved'or inclined deflecting sectionso that the gases and f products of combustion will bedirected by saidupper end of the arch wall, rearwardly and downwardly towards the fuelbed and interimtact with thefire door sheet 5. Any solid fine Iparticles of fuel carried in suspension by the gases are thus returnedto the jzone of intense heat where they will'be ignited. Thus, bycausing the. products of combustion to directly contact with andfiowupwardly along the firedoor sheet 5', a maximum percentage of the heatunits will be utilized in the conversion of the water into steam; Also,the products of combustion ar thereby caused toicomef into;directcontact with the rearend portion of. the crown sheet. 8, with theelongated 'portionsofthe siphons, and

as well with the portions I3 of the water circulating tubesha'vingarelatively extensive wall area. This further increases the maximumextraction of heat from the burning gases and the generation of steam inthe boiler.

While anypreferred' means may be provided for the purpose of retainingthe rear downward- .ly inclined; brick I4.of the arch upon the supportingshoulders IIfand ll,for thispurpose I prefer to 'weld' orotherwise permanently secure to the opposite sidesor thewatercirculating tubes and-siphons the short lugs or trunnions indicatedat I5 which effectively prevent thej rearwardsliding movement of thefire brick."

in Figs. 3 and 4 of the drawings, Ihaveshown an'auxiliary rear archspaced. from .the main arch wall For the purpose of supporting thisauxiliary arch in position; the side walls of the flattenedsections I3of the water, circulating tubes are formed withoutwardly struckribsgindicated at H which are inclined downwardly and rearwardlyacross'said tubes'towards the fire door sheet. 5. The rear ends of'thesiph'ons I6 relation to the ribs I1 and are suitably connected fwiththe rear endfwallsof thesiphons and the fire door sheet 5. "Upon thesetubes I8 and} the ribs I! of the adjacent main. arch supporting tubestheopposite ends oftherefractory brick .or'tile IQ-are supported. Th'esebrick-maybe of the same standard form asthebrick I4 con-1 stitutingthemain arch. The rear-brick I9 are spaced from the fire door sheet '5abymeans of suitable spacer brick indicated at 20,which' are arranged onthe tubes I8,'thu s'providing open- 35 are connected by watercirculating means with the fire door sheet 5, and in this instance, this7 Water circulating means is in the form of the tubes I8 which extendsubstantially in parallel 0 ings between. the "rear end :of the'archformed by the brick IQ -and the fire door, sheet. These spacer brick'maybe of any suitable length as' circumstances or conditions mayrequire; IIn thislast described form of the invention,

it will be understood that after the products of combustion are directedrearwardly andfdow'n- Wardly bythe upper endof the main arch wall.

against the fire door sheet, their upward course of flow along the firedoor sheet will be retarded by the auxiliary arch wall composedof thebricks I9, thussecuring a very intensive concentrated heating effect'upon the firedoorsheet 5. The products of combustion pass atrelativelylow velocity upwardly throughthe spaces in the auxil iaryarch'formedlby the spacer brick 20 and into contact with the rear endofthe crown sheet Where further heat. isextracted therefrom b efore theevaporation of the boiler water. Also by the provisionjof the tubularwater "circulating 'connections between the fire door sheet and'the rearendsof the siphon' s'. I6, better and freer circulation of the waterthrough the siphons is. obtained "the auxiliary arch and the fire doorsheet providcombustion is deflected into contact with the rear fire doorsheet, it will be understood that this feature isnot hereinbroadlyclaimed the principal feature of novelty in my present invention,residing in the novel construction of the water circulating tubes andsiphons, whereby the ad- 1 vantages of the invention disclosed in myoopending application may be obtained with the use ofarch wall brick ofordinary standard form throughout the structure of the arch.

I have herein shown several embodiments of the essential features of myinvention, but it is to be understood that the same might also beincorporated in various other alternative structural forms, and Iaccordingly reserve the privilege of adopting all such legitimatechanges therein as may be fairly incorporated within the spirit andscope of the invention as claimed.

' I claim:

1. In a locomotive boiler furnace, transversely spaced water circulatingelements having parts longitudinally inclined upwardly from the fire boxthroat sheet, an arch wall composed of refractorybrick, and said partsof the water circulating elements at each side thereof being formed withlongitudinally extending supporting shoulders for the arch brick havingtheir upper end portions downwardly curved towards the fuel bed, anauxiliary arch wall above and in rearwardly spaced relation from saidfirst named arch wall, and means associated with said water circulatingelements supporting said auxiliary arch wall in a longitudinallyinclined position extending rearwardly and downwardly towards the doorsheet of the fire box.

2. In a locomotive boiler furnace, transversely spaced water circulatingelements'having parts longitudinally inclined upwardly from the fire boxthroat sheet, an arch wall composed of refractory brick,-and said partsof the water circulating elements at each side thereof being formed withlongitudinally extending supporting shoulders for the arch brickhaving'their upper end portions downwardly curved towards the fuel bed,an auxiliary arch wall above and in rearwardly spaced relation from saidfirst named arch wall, means associated with said water circulatingelements supporting said auxiliary arch wall in a longitudinaly inclinedposition extending rearwardly and downwardly towards the door sheet ofthe fire box, and spacer brick interposed between ing passages for theupward fiow of the products of combustion in contact with the upper endof said door sheet and the rear end of the crown sheet of the firebox.

3. In combination with a locomotive boiler fire box and transverselyspaced water circulating elements extending through said fire box, saidelements including siphons connected with the fire box throat sheet andthe crown sheet and terminating at their rear ends in spaced relationfrom the door sheet of the fire box, a main arch wall supported by saidelements extending upwardly from the throat sheet and terminating inspaced relation from the rear ends of the siphons, and an auxiliary archwall and supporting means therefor connecting the rear ends of thesiphons with the fire box door sheet, said latter arch wall beingdisposed above and in rearwardly spaced relation from said main archwall.

4. In combination with a locomotive boiler fire box and transverselyspaced water circulat-.

ing elements extending through said fire box, said elements includingsiphons connected with the fire box throat sheet and the crown sheet andterminating at their rear ends in spaced relation from the door sheet ofthe fire box, a mainarch' wall supported by said elements extendingupwardly from the throat sheet and terminating in spaced relation fromthe rear ends of the siphons, water circulating tubular connectionsbetween the,

rear ends of the siphons and the door sheet of the fire box, other watercirculating elements extending rearwardly of the siphons and connectedwith said door sheet, and an auxiliary arch wall supported by the latterelements and said tubular connections above and in rearwardly spacedrelation from the main arch wall.

5. In a locomotive. boiler furnace which ineludes transversely spacedwater circulatingelements inclined in the direction of their lengthupwardly and forwardly toward the fire box door sheet from the fire boxthroat sheet, shoulders formed on saidelements in the direction of thelength thereof from said throat sheet and having their upper front endportions curved downwardly toward the fire box fuel bed, an arch wallcomposed of refractory brick supported on said shoulders including thedownwardly curved end.

portions thereof, extensions on certain of said elements extendingupwardly to the fire box crown sheet, their rear ends spaced a distancefrom the fire box fiue sheet and their front ends extending well beyondthe downwardly curved end of the arch wall but spaced from the fire boxdoor sheet, and extensions on certain other of said elements lyingbetween the projected outlines of the first.

